From the name of the original PDF file, I assume they keep it updated and change the name when they do, so this is its original location, and please let me know if you found the link broken - thanks.

There are a couple reasons why the cameras were put into place, according to the houstontx.gov site:

"Red light running is the leading cause of urban crashes according to the Insurance Institute for Highway Safety. In 2004, more than 900 people were killed and an estimated 168,000 were injured in crashes that involved red light running.

Houston-Galveston Area Council data indicate that red light accidents in the Houston area account for approximately $225 million per year in total comprehensive cost.

The City of Houston is committed to the safety of the community and dedicated to reducing preventable collisions at signalized intersections. Every year, there are thousands of crashes that occur due to motorists running red lights in Houston.

The City’s Red Light Camera Enforcement Safety Program uses state-of-the-art digital camera and detection systems installed at some of Houston’s most dangerous intersections for the purpose of decreasing the number of red light runners and reducing collisions."

Here's a preview of what it will look like if you happen to get caught running a red light at any of the above mapped locations:

JPEG Preview - Click to Enlarge:

Moral of the story, if you're driving through Houston, TX, and you happen to see a yellow light, you should probably STOP (for a change)!

In case you were wondering, I never did find the information I was actually looking for. I guess my Google-Foo just isn't what it used to be.